In the development of the present invention, it has been discovered that many previous mechanisms for applying foliar spray material do not effectively contribute to the obtaining of good coatings and to obtaining well-distributed coatings on foliage, with regard to each of the tops and bottoms of leaves. In other words, teachings from the prior art, so to speak, have proven to be ineffective for precise application. In the present invention, for example, it has been discovered that what works for a flattened stream of spray is not equally true for a conical spray pattern. Likewise, it has been found that a non-solid stream does not have the required spray characteristics, and that very specific controls are required to obtain a successful result by method and apparatus thereof.
Prior to the present invention, application of liquid composition by foliar spraying has been inconsistent, producing poor results. Inconsistent results were obtained by Garcia and Hanway, 1966--"Foliar Fertilization of Soybeans During the Seed-Filling Period"; Agronomy Journal 68(4): 635-657. Himel stated that the efficiency rate for pesticide is usually less than one percent, 1982--Himel, C. M., "Analytical Systems for Pesticide Spray Transport and Impingement"; American Society of Agricultural Engineers Paper No. 82-1001.
Prior also to the present invention, there has been some experimentation involving various apparatuses and blowers for application of spray in foliar spraying, but as noted above, with limited success. For example, air blast sprayers have been used on row crops in some experimental work, by Kahn, A. S., T. G. Carpenter and D. L. Reichard, 1981--"Variables Affecting Spray Deposit Efficiency of a Row Crop Airblast Sprayer", American Society of Agricultural Engineers Paper No. 68-149. These row crop row blast sprayers spray several rows at one time from one air and fluid outlet point. A type of single row air blast applicator was developed by farmer Bruce Viker and has been tested with herbicides in terms of percent control--Roehl, L. J. 1982, "Row Crop Spray Evaluation", American Society of Agricultural Engineers Paper No. 82-1007. Other sprayers have used an air stream to atomize the spray material--(1) Wilkes, L. H. 1961--"Effects of Nozzle Types and Spray Application Methods on Cotton Insect Control", Transactions of the ASAE 4: 166-169; and (2 ) A. Zucker and N. Zamir, 1984--"Air Carriers Sprayers for Cotton", Journal of Agricultural Engineering Research 9: 188-193. In contrast to spray method and apparatuses thereof, the present invention has taken a novel approach in its method and apparatus.
Prior to describing the present invention, it is noted that for entirely different and unrelated fields and for different purposes having no relationship nor bearing on specific beneficial results achieved in this invention in foliar spray application, there have been apparatuses for spraying and applying paints, varnishes and the like, such an U.S. Pat. No. 1,897,173 by R. Long et al. granted Feb. 14, 1933, and U.S. Pat. 2,051,210 by E. Gustafsson granted Aug. 18, 1936, and U.S. Pat. No. 3,252,657 by D. D. Winegar granted May 24, 1966, and U.S. Pat. No. 4,236,674 by George Dixon granted Dec. 2, 1980. A mere air-nozzle that is non-spraying is covered by U.S. Pat. 4,050,632 to Harold G. Wyse granted Sept. 27, 1977.